The invention relates to an orthotic shoe sole insert and in particular an insert for correction of the human foot disorder, generally known as cavovarus foot.
Although many orthotic devices are provided for insertion into the shoe, the vast majority of these inserts are custom made or manufactured to correct the human flat foot. The typical orthotic insert does not alleviate the human foot disorder, generally known as a cavovarus foot. In this disorder, the foot assumes a posture of an inward tipping of the heel (heel supination or varus), and a related forefoot pronation (forefoot valgus). Further with this foot disorder the first metatarsal is plantarflexed and the arch is excessively high (cavus). This disorder results in the chronic inversion sprains of the ankle and subtalar joint, which can result in surgical reconstruction. The disorder may also cause a common stress fracture to the fifth metatarsal as well as stress fractures to the other metatarsals. Other injuries that can result from a cavovarus foot include recurrent dislocation or subluxation of the peroneal tendons, peroneal tendonitis, peroneal tendon splitting, overload callous under the base or head of the fifth metatarsal, metatarsalgia, hallux sesamoiditis, excessive external rotation of the talus and tibia resulting in varus strain of the knee joint, compressive medial compartmental knee overload and arthritis, and increased lateral collateral knee ligaments and iliotibial tract strain and tendonitis. A painful plantar fasciitis may also occur and with longstanding cavovarus foot deformities. A very painful varus ankle arthritis may develop, necessitating ankle arthrodesis (fusion), or total ankle arthroplasty (replacement). Other stress related disorders may occur to the ankle, knee, hip, and spine.
Most orthotic shoe inserts address the human foot disorder known as xe2x80x9cflat foot.xe2x80x9d With this disorder the arch of the foot is collapsed into a lowered position. The flat foot inserts are generally designed to push upwardly on the naviculocuneiform area and to support the collapsed medial longitudinal and transverse arches, or by placing additional material in the area between the dorisiflexed metatarsal and the shoe, forming a medial forefoot wedge. Other designs for orthotic inserts either simply conform to the bottom of the foot with metatarsal pads placed proximal to certain metatarsal heads to relieve the force on these areas, or the inserts have hollowed out portions under areas of pressure in the plantar surface of the foot.
The invention addresses the aforementioned concerns by providing a removable insert for a shoe directed to patients with high arches. In one aspect of the invention, a full length orthotic shoe sole insert is provided for overlying the sole of a shoe of a patient having a high arch and adapted for aligning the foot during movement by providing a small built up heel base portion in the insert, with a midfoot portion of having an arched area lower than the arch of the patient, and a forefoot portion, wherein the forefoot portion has a built-up portion beginning lateral to the head of the first metatarsal and lateral sesamoid of the foot.
In another aspect the build up portion of the forefoot portion of the insert has a constant thickness beginning just lateral to the first metatarsal head and lateral sesamoid.
The shoe sole insert may also include a valgus wedge starting in the transverse arched region of the foot. The valgus wedge may thicken laterally beginning proximal to the lateral first metatarsal head and increase in elevation distally from the heel portion. Further, the insert may have a depression for receiving the first metatarsal head of the foot.
In a further aspect of the invention the insert is sized to the patient by measuring from the posterior heel of the foot to the first metatarsal head, rather than from the heel to the end of the toes.